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1.
Recreational activities can have major impacts on vegetation and wildlife in frequently visited forests. We assessed forest perception and knowledge (state, functions, and species diversity) among hikers and mountain bikers in a frequently visited, seminatural suburban recreation forest (Muttenz) and in a more distantly situated, naturally grown excursion forest (Wasserfallen) in northwestern Switzerland. In all, 239 hikers and 126 mountain bikers were interviewed. Mountain bikers in both forests and hikers in the more intensely used recreation forest at Muttenz assessed the state of the forest less optimistically and showed a higher awareness of the negative impact of recreational activities on the flora and fauna than hikers at Wasserfallen. Furthermore, mountain bikers seemed aware of the social conflicts caused by their activity, since they appreciated neutral or positive encounters with other forest visitors. In contrast, 57% of hikers at Muttenz reported on negative experiences with other forest visitors, particularly with mountain bikers. In general, the interviewees ecological and biological forest knowledge (forest type and function, species diversity) was rather high. A large proportion was aware of the pros and cons of different forest conditions for plants and animals, and could name or recognize at least some plant and/or animal species typical for the visited forest. The forest knowledge was neither influenced by the type of recreational activity carried out nor by any aspect of forest visit behavior (frequency and duration of forest visits, means of transportation and travel distance to forest). However, the interviewees forest knowledge was influenced by their age and educational level.  相似文献   

2.
Biotechnology applied to traditional foodanimals raises ethical issues in three distinctcategories. First are a series of issues that arise inthe transformation of pigs, sheep, cattle and otherdomesticated farm animals for purposes that deviatesubstantially from food production, including forxenotransplantation or production of pharmaceuticals.Ethical analysis of these issues must draw upon theresources of medical ethics; categorizing them asagricultural biotechnologies is misleading. The secondseries of issues relate to animal welfare. Althoughone can stipulate a number of different philosophicalfoundations for the ethical assessment of welfare,most either converge on Bernard Rollins principle ofwelfare conservation (Rollin, 1995), or devolve intodebates over the ethical significance of animaltelos or species integrity. The principle of welfareconservation prohibits disfunctional geneticengineering of food animals, but would permit alteringanimals biological functions, especially when (as inmaking animals less susceptable to pain or suffering)do so improves an individual animals well being.Objections to precisely this last form of geneticengineering stress telos or species integrity asconstraints on modification of animals, and thisrepresents the third class of ethical issues. Most whohave formulated such arguments have failed to developcoherent positions, but the notion of species being,derived from the 19th century German tradition,presents a promising way to analyze the basis forresisting the transformation of animal natures.  相似文献   

3.
This paper investigates the relationship between pupils' environmental perception (in terms of preservation and utilisation of nature) and personality (in terms of risk-taking). 713 secondary school pupils in Switzerland were investigated. Environmental perception was assessed via three factors: Preservation, Utilisation of Nature and Consideration for Conservation. Risk-taking was evaluated via six factors: Positive Risking, Ambivalence, Thrill in Gambling, Ineffective Control, Effective Control, and Anger Reaction. Analysis of the correlation matrix between Risk-taking and Environmental perception revealed three profiles (types): the high scorer on Preservation is the controlled and cautious gambler. The Utiliser (anthropocentric) profile is essentially a mirror image of the first: the Utiliser does not enjoy unpredictable risks, reacts with anger when risks fail and has little control over his/her own risk-taking behaviour. The Consideration for Conservation (ecocentric) profile assumes a position between these two profiles.  相似文献   

4.
India has 2.34 million km2 of hot desert called Thar located in the north-western part of Rajasthan between latitudes 23°3 and 30°12 North and longitudes 63°30 and 70°18 East. The Indian desert is spreading annually over 12000 ha of productive land degrading it and slowly advancing towards the national capital New Delhi at the rate of 0.5 km per year. The Indian desert is characterised by huge shifting sand dunes; high wind speed; scarce rainfall; and intense solar radiation. Tremendous efforts have been made since the 1960s to arrest desertification and for ecological restoration of the Thar desert. An Ambitious afforestation programme including stabilisation of shifting sand dunes and creation of micro-climates through tree-screens and shelter-belt plantation was launched by the forest department of Rajasthan. A huge canal, 649 km long was also introduced to the Thar desert for ecological restoration.  相似文献   

5.
Due to assimilation of recycled CO2 from litter decomposition and photosynthetic changes in carbon fractionation at low light levels, the foliage at the base of a forest is often more depleted in13C compared to that exposed to the atmosphere in either the canopy or in open clearings. This is referred to as the canopy effect. African research has indicated that these habitat differences in foliar 13C can be substantial enough to affect the carbon isotope ratios of resident fauna. Previous work documenting a 30-year chronology on moose teeth from Isle Royale National Park indicated a progressive depletion in13C and suggested that this could be due to forest regrowth following extensive burning. The present study examined the assumption implicit in this hypothesis that foliar 13C varies between open and closed boreal forest sites. I found a marginal canopy effect of 2 13C difference between upper canopy and ground flora for a forest in northwestern Ontario and an average difference of 1.2 in under- and mid-story vegetation between closed forests and open clear-cuts. Because of these small differences, the utility of carbon isotope analysis in quantifying temporally integrated exploitation of deforested habitats will be low for northern boreal locations. In denser forests, such as those in the tropics or western North American where the canopy effect can be expected to be much greater, 13C analysis may still offer some promise for determining selection by wildlife of disturbed habitats.  相似文献   

6.
A large proportion of existing species — possibly half, conceivably even more — may be lost within the foreseeable future. But this may not prove to be the most consequential outcome of the current biodiversity crisis. More significant could be the disruption and degradation of several basic processes of evolution. It appears likely that for mass extinction episodes (MEEs) in the geological past, the recovery period usually lasted at least five million years. Because of certain unique features of the present MEE — notably the near elimination of biomes such as tropical forests, wetlands and coral reefs, which have served as powerhouses of evolution in the past — the bounce-back phase could extend several times longer than five million years. Among distinctive features of future evolution could be; in the short term, homogenization of biotas, a proliferation of opportunistic species, an outburst of speciation among particular taxa, and a pest-and-weed ecology; and, in the long term, a decline of biodisparity, the elimination of megavertebrates, an end to speciation among large vertebrates, and multiple constraints on origination, innovation and adaptive radiation. These disruptive phenomena would rank among the most prominent departures in the entire course of evolution. Full knowledge and understanding of what may characterize future evolution remains largely a black hole of research. As a consequence, conservation policies fail to reflect a further problem of the biodiversity prospect, perhaps exceeding the better recognized problem of the mass extinction of species.Professor Norman Myers is an Editorial Board member and regular contributor toThe Environmentalist. He is an Honorary Visiting Fellow at Green College, Oxford. This paper is a greatly expanded version of a preliminary probing in a popular magazine a decade ago (Myers, 1985). It has been prompted by a major international conference organized by the US National Academy of Sciences, scheduled for late 1996.  相似文献   

7.
Oregons land-use planning program is often cited as an exemplary approach to forest and farmland conservation, but analyses of its effectiveness are limited. This article examines Oregons land-use planning program using detailed spatial data describing building densities in western Oregon. An empirical model describes changes in building densities on forest and agricultural lands from 1974 to 1994, as a function of a gravity index of lands commuting distance to cities of various sizes, topographic characteristics, and zoning adopted under Oregons land-use planning program. The effectiveness of Oregons land-use planning program is evaluated based on the statistical significance of zoning variables and by computing estimated areas of forest and agricultural lands falling into undeveloped, low-density developed, and developed building density categories, with and without land-use zoning in effect. Results suggest that Oregons land-use planning program has provided a measurable degree of protection to forest and agricultural lands since its implementation.  相似文献   

8.
The paradigm of sustainable tourism is discussed in terms of analysing what it actually means. Certain questions are raised and these include the means of its measurement, the question of intergenerational impacts and how these may be assessed, the determination of what exactly is meant by environment, the aspect of tourism as an industry and, with specific reference to tourism in the developing world, the potential for neocolonialism. It is argued that, although sustainable tourism may be a worthwhile goal, inherent problems in the definition and measurement of its success make it an elusive if not academic target. The challenge of sustainable tourism is to see it in a broader context as but one tool of development and to ensure that it is examined in the context of the local community as well as a global perspective.  相似文献   

9.
Arsenic levels in seawater, microplankton (diatoms and dinoflagellates), shrimp (Penaeus semisulcatus), mollusc (Cerithium scabridum) and five types of fish (Maid, Nakroor, Nuwaiby, Suboor and Sheim) in five sampling stations (I–V) off the Kuwait coast were determined during the years 1995 to 1999. The maximum mean concentration of arsenic was observed in the order; the five fish (0.50–0.78 g g–1)> mollusc (0.26 g g–1)> shrimp (0.23 g g–1)> particulate matter (0.03 g g–1)> water and phytoplankton (0.02 g g–1) from all the sites of the Kuwait coast. Station II possessed the maximum arsenic levels. In comparison with the arsenic levels in other parts of the globe, low arsenic levels were observed in most of the marine organisms off the Kuwait Coast. However, an increasing trend in arsenic concentrations was anticipated due to rapid local industrialization and on account of recent spills of arsenic compounds.  相似文献   

10.
Tutor in the Department of Geography at the University of Western Australia. In response to the fragmentation and loss of indigenous vegetation caused by the expansion of metropolitan Perth, all levels of government in Western Australia have made some commitment to the preservation of biodiversity. A case for seeing and using vegetation structure as a possible surrogate for biodiversity is presented. The concept and a simple methodology which may be applied without any specialist ecological knowledge or expertise is outlined for the urban developer, engineer, planner, decision maker and educator. The notion that the degree of diversity of the vegetation structure of a banksia woodland remnant may indicate and give a substitute or preliminary measure of biodiversity assists the popular understanding of biodiversity. Such a non-technical yet objective appreciation and measure may prove satisfactory for some conservation purposes, until a detailed professional assessment is made of the plant and animal species in a remnant of native vegetation. It is currently being used by state planning staff in Western Australia for the preliminary assessment of native woodland in areas zoned for urban growth at the metropolitan fringe.  相似文献   

11.
The composition of the herbaceous cover and the seed bank of old and recent hedge banks in Brittany were studied and compared. Concentration method was used for seed bank samples. Grimes plant strategies were used to explain observed patterns. The analysis of the seed bank of these hedge banks showed that the species richness and diversity differed in relation to the date of construction of the hedge banks. The seed banks of recent hedge banks were richer and more diversified than those of old hedge banks. Differences in the floristic composition of the established plant cover between the recent and old hedge banks were determined by multivariate analyses. The species exclusively found in the seed bank and in the herb cover of recent hedge banks were mainly grassland species, whereas the species that only occurred on old hedge banks tended to be woodland species. The floristic composition of the two compartments (established vegetation and seed bank) was very different. A multivariate analysis revealed that the difference between the composition of the seed banks of recent and old hedge banks was less than that between the composition of the established vegetation and seed bank of hedge banks of the same age. Both seed bank and vegetation of recent hedge banks were dominated by ruderal species, whereas old hedge vegetation was dominated by stress-tolerant woodland species, indicating that mechanically constructed hedge banks may impose limitations on colonization by late woodland species.  相似文献   

12.
Summary Noting a paucity of sociological research investigating countryside recreation from an experiential perspective, this paper reports on a study aimed at exploring the meaning of such terms as the countryside, rural and natural as they are understood by the person-in-the-street. A typification of countryside recreation is constructed which suggests that individuals have an essentially simple understanding of the environment in this context which centres upon an urban-rural dichotomy. The urban setting is generally associated with negative experiences while the rural setting is regarded more positively. These attitudes suggest that the countryside represents a form of refuge from many stresses commonly associated with modern, urban lifestyles. An implication of this conclusion is that attempts to educate people into recognizing the links between their everyday behaviour and the degradation of the countryside will be met with considerable resistance since this would entail them in reconstruing their relationship with the environment.  相似文献   

13.
Environmental knowing includes the very many bodies of formal theory which have some relevance to the environment, as well as the knowing which comes from experience in the environment. This knowing can be seen as informing action both conceptually and instrumentally. This paper presents a multidisciplinary and transdisciplinary approach which can inter-relate these many knowings in a way which is relevant to and contingent on definition of particular environmental problems. This problem-focused approach involves application of a set of questions which are implied by a taxonomy of ignorance. The paper shows how the approach can inter-relate knowings as diverse as Taoism and energy-efficiency standards, with the purpose of informating environmental action.  相似文献   

14.
Summary The private enterprise development of a series of disused gravel pits, situated just 20 miles from the centre of London, into an attractive and commercially viable theme park for leisure and recreation is described.

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15.
Assistant Professor in Human Ecology, in the Indira Gandhi Centre for Human Ecology, Environment and Population Studies at the University of Rajasthan. Although fluorine is an essential element for human growth and development, its intake in excessive amounts beyond the permissible limits can be very harmful. Dental and skeletal fluorosis are some of the common afflictions of fluorine poisoning and it can even have crippling effects in aged individuals. With the rise in industrialization fluoride contamination is increasing in the human environment as it is a basic component of the ground water. Certain regions of India, particularly the arid zones of Rajasthan, have serious fluoride problems and it has become a serious health hazard in several villages of Rajasthan.  相似文献   

16.
The snowmobile controversy in Yellowstone National Park not only pits snowmobilers against environmentalists, but it also pits the Bush Administration against the Clinton Administration. Caught in the middle are the National Park Service, scores of natural and social scientists, and Yellowstones permanent residents—the flora and fauna. The controversys political aspects are the focus of this paper; specifically, the tenuous relationship among research scientists, whose job it is to inform management and policy decisions; politicians, whose job it is to formulate those same decisions in the public arena; and public land management agencies, whose job it is to implement the decisions. The crux of the paper concerns the politicization of natural resource policy and ways in which research scientists tend to get caught up in it. Lessons learned from this Yellowstone episode regarding the role of science in policy-making processes are also considered. Two recent federal court rulings shed additional light on the politics surrounding Yellowstones snowmobile controversy, as does the importance of governmental checks and balances in resolving natural resource management disputes.  相似文献   

17.
Summary Technological optimism is the doctrine that a growing number of technological improvements in such areas as food production, environmental quality and energy will sustain life as human population soars. It evolved as a response to the Malthusian study The Limits to Growth (The Club of Rome, 1972). Like population biologist Paul Ehrlich, Professor James Krier of the University of Michigan Law School believes that the technological optimists may be wrong. Krier describes how the marginal costs of pollution control increasingly rise. He faults biologist Barry Commoner for neglecting population growth as the cause of pollution and positing the postwar technological transition as its cause. He argues that population growth forced this transition as science searched for substitutes for dwindling resources. Krier criticises as an article of faith the technological optimists' belief that S-curve patterns of technological advance will always arrive in response to the J-curve of exponential population growth. He thinks that the technological optimists may be deluding humanity by predicting the continual emergence of technological breakthroughs at ever-increasing rates. He favours growth policies that would allow humanity to ease into a steady state of resource use and minimise the maximum cost, which would be a global crash after technological innovation fails. Krier laments that modern technolgy can worsen pollution and invites problems of latency, irreversibility, zero-infinity risk and remoteness. He thinks that approapriate technologies which have failed economically may fail politically because the political process has been captured by opposing interests. Krier urges that the population crisis should be adressed insteadAndrew D. Basiago is a graduate of UCLA and Northwestern School of Law's environmental law programme. As writer, lawyer and environmental planner he has written articles about ecology for the Cousteau Society and interviewed such luminaries as R. Buckminster Fuller, Amory B. Lovins and  相似文献   

18.
Summary Human beings use huge quantities of water every day for drinking, cleaning and various cultural functions and dispose of it as wastewater within sewage. With increase in population, the magnitude of this waste is multiplying enormously and beyond the recycling capacity of local ecosystems to become a major health and environmental hazard. Re-use of wastewater for afforestation purposes in the form of sewage silviculture combines the dual benefit of water conservation with environmental sanitation. Such experiments are being carried out at the World Forest Arboretum in Jaipur, Rajasthan, India. Biological treatment of the sewage before application, to improve its irrigational quality, to remove harmful chemicals and to prevent the risk of these passing into the human food chain is being undertaken. The aquatic weeds Lemna and Eichhornia are being used to purify the wastewater. The technique is both economically viable and ecologically sustainable.Dr Rajiv K. Sinha is assistant professor in Human Ecology at the University of Rajasthan.  相似文献   

19.
Chapter 36 of Agenda 21 called on each nation to bring together a widely cross-sectoral group of people to prepare a national strategy for environmental education and training. In Scotland this process had already begun and the Secretary of State's Working Group on Environmental Education presented him with its recommendations for a strategy in April 1993, which he accepted in a statement of intent in June, 1995. The process itself, the comments received on the report since publication and continuing developments in the field, have demonstrated the importance of adopting broad definitions for both environment and education, spreading involvement in production of the strategy to all sectors and as wide a range of individuals as possible, dividing up the work so as to focus on all the main contexts in which learning takes place, working with the main potential implementers and not depending entirely on the availability of new resources. The process was in itself rewarding and its importance should not be underestimated. The approach adopted and the issues which it raised appear to have wide applicability to similar programmes elsewhere. This paper describes the process adopted in preparing the strategy, reviews some of the subsequent developments in Scotland, and assesses the factors which may have contributed to its success so far.Professor John C. Smyth, OBE is Emeritus Professor of Biology at the University of Paisley. He is President of The Scottish Environmental Education Council and he presented this paper at the Global Forum '94 Academic Conference Towards a Sustainable Future: Promoting Sustainable Development, Manchester, UK.  相似文献   

20.
Summary The Greek natural environment shows an extensive diversity of flora and fauna and a significantly high density of important biotopes. This notable ecological wealth is threatened with rapid degradation caused by human activities. Its protection through nature conservation measures and through the control of development projects and activities is obstructed by factors such as the existence of a large number of non-point sources of disturbance which are related to a large number of people, the inefficiencies of State mechanisms, the indifference of local societies with regards to planning procedures and long-term social benefits, and a traditionally indifferent or hostile attitude of countryside people towards nature. A study of the threats against the natural environment shows that the most important of these derive from activities that bring people closer to nature, but which follow a development model that is not sustainable. Such activities are: farming, animal grazing, fishing, tourism, vacation house-building, the opening up of roads, hunting, motorized recreation, etc. Contrary to this, the development of industry and the big enterprises of the tertiary sector appears more compatible with the preservation of a rich natural environment when certain conditions such as effective control, use of modern technology and convergence of business and environmental benefits occur. Consequently, this kind of development shows a better perspective as a sustainable development.Kimon Hadjibiros is a physicist-cum-ecologist working at the National Technical University of Athens. This paper, like others in Volume 15, No. 4 ofThe Environmentalist, was presented at the Global Forum '94 Academic Conference Towards a Sustainable Future: Promoting Sustainable Development, Manchester, UK, in June, 1994.  相似文献   

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